1. Field of the Invention
The present invention relates to a driving apparatus which utilizes an electro-mechanical conversion element such as a piezoelectric element, and more particularly to a driving apparatus for driving an optical member such as a small lens which is installed on a small digital camera, a web camera or a mobile phone with a camera.
2. Description of the Related Art
The related-art lens driving apparatus which utilizes a piezoelectric element is described in, for example, JP-A-7-274543. The driving apparatus, which is described in the Japanese patent unexamined publication, is a unit for moving a lens barrel in which a driving shaft is held by the lens barrel and a friction plate therebetween, so that the lens barrel, which is a driven member, is brought into frictional engagement with the driving shaft. In addition, in this driving apparatus, the driving shaft is supported by being passed through a through holes provided in a supporting plate.
The related-art driving apparatus has, however, the following problem. Namely, in order to improve the workability in passing the driving shaft through the through hole, the cross-sectional dimension of the through hole needed to be designed to be larger than the cross-sectional dimension of the driving shaft. When such a design was adopted, the support of the driving shaft by the supporting plate could not be implemented with good positional accuracy, thereby interrupting the stable driving properties of the driving apparatus.